FYI from PayPal Developer Network's Live Site Status blog:
(Live Site-536)  Scheduled - Scheduled Maintenance - Jan 08
12-22-2008 10:54 AM
PayPal_Updates PayPal_Updates Administrator writes...
 Scheduled: This notification is to inform you of a Database Maintenance activity.
- From Jan 08, 11:00 PM PST (Jan 09, 7:00 AM GMT) to Jan 08, 11:44 PM PST (Jan 09, 7:44 AM GMT):The following will be available:
1. PayPal Account Optional with these exceptions
. NO login
. NO password recovery
. NO save info
. NO PDT
2. Website Payment Standard and Express Checkout
. Allows user login
. Supports the user's current funding sources
. NO add CC
. NO add bank
. NO add address
. NO sign-up
3. Express Checkout with Account Optional
4. DCC(Sale & Auth)
5. Risk Controls
6. IPN will also be delayed.
- From Jan 08, 10:30 PM PST (Jan 09, 6:30 AM GMT) to Jan 09, 3:45 AM PST (Jan 09, 11:45 AM GMT): All batch processing will be put on hold and released after the activity, which means no batch capture/refund will be available during this time.
- Pacific timezone reports may be delayed on January 9th.
(Sent Dec 22, 10:48 AM PST by PC)
SCHEDULED MAINTENANCE DETAILS
Service: Live Site
- Order Management (IPN / PDT)
- Batch Processing
- Express Checkout
Start Time: Jan 08, 11:00 PM PST (Jan 09, 7:00 AM GMT)
End Time: Jan 08, 11:40 PM PST (Jan 09, 7:40 AM GMT)
Our Technology team advises during this period some products and features may be temporarily unavailable. We are working to ensure the inconvenience is as minimal as possible.
We apologize for any impact caused by this maintenance.
PayPal Merchant Technical Services
If you have questions, contact PayPal Merchant Technical Services by filing a ticket under contact support (refer to ID: Live Site-536) at https://www.paypal.com/mts/.